Usually within a day of opening escrow.
That is, after you reach an agreement with the home seller (perhaps after a few counter offers back and forth along the way), I will take the signed contract including all counter offers, addendums, and your earnest money check to the escrow company named in the contract. I do this the next business day after an purchase agreement is reached.
The escrow company will cash your check that day or the next day. The funds will be deposited into your escrow account at the escrow company.